Novel Detection Methods Of Sudan I And Their Applications

Sudan I is a genotoxic carcinogen and its presence is not permitted in foodstuffs for any purpose at any level. In this context, the rationale is on the basis that this colourant could be found in some food products, because of its intense red orange colour. For this reason, sensitive, selective and accurate analytical methods should be developed in order to identify and quantify such substance. As reported in the literature, dealing with the analytical chemistry of Sudan I, several methods were developed to detect the presence of this compound, however, some existing methods of equipment demanding. In this work, we studied the mechanism of the sudan I with HSA, proposed three novel methods to concentrate, purify and detect this substance.In the chapter 1, a novel detection has been developed for Sudan I based on the fluorescence quenching effect . The fluorescent quenching value of HSA at 337nm was linear to the concentration of Sudan I in the range of 0.47⁷.50μg/ml, at 25℃, in the Tris-HCl buffer solution (pH8.2) with the detection limit was 0.14μg/ml. The RSD was 0.70%¹.78% and average recovery was 91.90%¹09.33%. The proposed method was sensitive and simple, succeeded in the spiked hot chilli samples .In the chapter 2, the interaction of Sudan I with HSA was studied by means of steady state fluorescence quenching spectroscopy. The results showed that the combination constant K was 8.30×10⁵, and the number of binding sites n was 1.27 (t=25 ℃) . The transfer efficiency of energy and distance between Sudan I and HSA were obtained (E was 0.76, R₀ was 2.45nm, r was 2.02nm) based on the mechanism of Forster energy transfer. The main sort of binding force can be obtained according to the thermodynamic parameters.